Explanatory Notes
Draft Queensland Development Code, Mandatory Part 1.4 –
Build over or near sewers, stormwater drains and water mains
(draft QDC)
Background
Sewer or water mains
Section 192 of the Water Supply (Safety and Reliability) Act 2008 (WS (S&R)
Act) states that a person must not, without the written consent of a service
provider, interfere with the service provider’s infrastructure. This requirement
is reflected in section 83 of the Building Act 1975 (BA) which provides that a
private certifier must not grant a building development approval if the
proposed building work is over or adjacent to sewer or water main until
consent under the WS (S&R) Act has been granted.
The WS (S&R) Act does not specify the criteria that must be addressed by a
service provider, or the process to be followed, when making an application.
There are also no consistent mandatory design standards to provide
information on whether it is appropriate to build over or adjacent to a service
provider’s infrastructure services.
Some local governments require a planning development application for
building work over or near sewer and water mains, even though consent is
required under the WS (S&R) Act.
The current process for appealing decisions related to consent to build over or
adjacent to a sewer or water main is under the WS (S&R) Act. It provides for a
process of internal review and then external review to the Queensland Civil
and Administrative Tribunal (QCAT).
Stormwater drains
Section 83 of the BA does not require consent for building work over or
adjacent to a stormwater drain. Stormwater drains are administered under the
Local Government Act 2009. Stormwater drains are owned either by a local
government or a private lot owner and there is no consistent process across
the state about how this type of building work is regulated.
2011 consultation process
Building Newsflash number 480 was issued on 19 September 2011 and
sought public comment on a proposal to mandate a revised version of the
current Queensland Development Code Non-Mandatory Part (NMP) 1.4 –
‘Excavation and Piling near Sewers, Stormwater Drains and Water Mains’
(NMP 1.4). The suggested process was to specify that building certifiers
would oversee building work that complied with the acceptable solutions of
the code. Concurrence advice from local governments or water service
providers would be needed for building work that used a performance solution
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to comply. The Building and Development Dispute Resolution Committees
(BDDRC) would hear appeals on these matters.
Following consultation, the Department of Housing and Public Works (DHPW)
has now revised the QDC 1.4. It is proposed to adopt the revised QDC 1.4 as
a new QDC Mandatory Part 1.4 (draft QDC) which will provide detailed criteria
for building work over or near a service provider’s infrastructure services.
Policy objectives and the reasons for them
The purpose of the draft QDC is to provide that building work over or near an
existing infrastructure service does not damage those services and the
associated structures. It will also provide that access to the infrastructure
service is available for ongoing maintenance and repairs.
The draft QDC is also aimed at providing timely and consistent assessment of
building work over or near an infrastructure service across Queensland. In
addition, the proposed changes will provide for a more simple and costeffective appeal process.
The current regulatory process for building over or near an infrastructure
service is complex and approval mechanisms are not uniform across
Queensland. An application may require assessment against the BA, the WS
(S&R) Act and a planning scheme.
Under this proposal, it is expected that there will be a reduction in red tape for
applicants, as building work over an infrastructure service will only need to be
assessed against a single standard under the draft QDC. The standard will
apply across the state, which will provide certainty and consistency.
The proposed changes will clarify that building work over or near an
infrastructure service is assessed under the BA as part of the building
assessment provisions. By virtue of section 78A of the Sustainable Planning
Act 2009 (SPA) and section 31 of the BA the provisions of the draft QDC will
prevail over a local planning instrument that includes such provisions.
Local governments (and other service providers or water entities) will have
powers to direct outcomes of applications for building work that do not comply
with the acceptable solutions of the draft QDC through the referral agency
process. The BDDRC will have jurisdiction to hear appeals from decision of a
referral agency.
Achievement of policy objectives
The draft QDC provides performance requirements and acceptable solutions
for the design and construction of all new building work over or near a service
provider’s infrastructure services, and incorporates access provisions to
enable infrastructure services to carry out maintenance and repair.
A private certifier will assess a building development application against the
draft QDC. It will no longer be necessary to obtain consent from a service
provider for this part of the building construction (i.e. load-bearing footings,
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suitable access to services for repairs or maintenance). If the application is
consistent with the draft QDC, nothing further will be required.
If the application does not comply with the acceptable solutions in the draft
QDC, a concurrence agency response will be triggered. The draft QDC
provides that the local government, water entity or service provider will be the
concurrence agency (note, that for South-east Queensland, only local
governments will be concurrence agencies until 2013, as these local
governments are delegates for service provides for development applications
until that time).
It is proposed that the acceptable solutions of the draft QDC will only apply to
building development applications for class 1 buildings (such as houses and
townhouses) and class 10 buildings or structures (such as sheds and
retaining walls). Acceptable solutions are further limited to circumstances
where the size of the infrastructure pipe is up to 225 millimetres in diameter.
If the building development application does not comply with the acceptable
solutions provided by the draft QDC, a concurrence agency response will be
triggered to consider an alternative solution.
Limiting application of the acceptable solutions to building work associated
with these simpler buildings and structures will also provide cost efficiencies
for local governments, by reducing the number of applications that they will
need to review.
As building development applications for class 2 to 9 buildings (such as units,
offices, shops, warehouses etc.) are more complex, they will, in all cases,
need to be referred to the relevant service provider as a concurrence agency
under the Sustainable Planning Regulation 2009 (SPR). Once referred by a
building certifier, the concurrence agency will assess the application against
the performance requirements of the draft QDC.
Referral Agency
A concurrence agency response will be triggered where the building is a class
1 or class 10 building or structure and an alternative solution is required to
meet the performance requirements because the proposed building work
does not comply with the acceptable solutions. In that case, the application
must be referred to a concurrence agency (the service provider, water entity
or local government) who will direct the outcome of the building development
application (approve, approve with conditions or refuse).
Referral to a concurrence agency will automatically occur for applications
involving class 2 to 9 buildings or where larger infrastructure services (i.e.
pipework exceeding 225 millimetre diameter) are present.
Disputes/Appeals
The current process for appealing decisions related to building over or
adjacent to an infrastructure service is in the WS(S&R) Act and provides for a
process of internal review and then external review to QCAT. This process
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causes costly delays and added expense to building work. The BDDRC can
provide a quick and cost-effective dispute resolution service for applicants
dissatisfied with decisions made by a service provider, local government or
certifier.
Appeals to the BDDRC are heard by referees with appropriate expertise.
Notes on provisions
Purpose
The purpose of the draft QDC is to provide:
 building work over or near existing services and associated structures
does not damage those services or associated structures; and
 access to those services and associated structures is available for ongoing
maintenance and repair.
Commencement
Subject to approval by government, it is anticipated that draft QDC will
commence in late 2012.
Application
The proposed draft QDC will apply to all building classes and structures on
sites containing sewer or stormwater drainage lines or water mains (other
than the associated house drainage and water supply pipes).
Limitation
The proposed draft QDC will not apply to an infrastructure service where there
is an easement right registered with the Queensland Land Titles Office
relating to the infrastructure service.
Referral agency
Where an alternative solution is being used to meet the performance
requirements of the draft QDC with respect to a class 1 or a class 10 building
or structure, a concurrence agency response will be triggered.
Acceptable solutions of the proposed draft QDC will apply to building work
where the service pipes are 225 millimetre diameter or less. This is the
standard size for service pipes and a larger diameter would require more
detailed engineering analysis. Where the pipe work exceeds 225 millimetre
diameter, the application will be referred to the relevant agency for
concurrence advice.
A concurrence agency response will also be triggered for class 2 to 9
buildings.
Concurrence agencies will be the local government, water entity or the service
provider. Note, however, that for South East Queensland, only local
governments will be concurrence agencies until 2013, as these local
governments are delegates for service provides for development applications
until that time).
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Compliance with the QDC
As with all assessable building work, compliance can be obtained in a number
of ways, including by compliance with the relevant acceptable solution for the
performance requirement, formulating an alternative solution that complies
with the performance requirement or a combination of the two (refer section14
of the BA).
Definitions
Some of the important definitions in the draft QDC are:
Structure: includes the meaning given by the Building Act 1975 but also
includes for the purposes of this Part, a retaining wall, deck, pergola,
swimming and spa pool, and water storage tank or the like.
This definition is particularly important for structures such as retaining walls or
masonry walls in the vicinity of infrastructure services. Both buildings and
structures are required to meet the performance requirements which protect
infrastructure services. The definition is designed to capture all relevant
entities for the connection point to a service.
Zone of influence: of a building or structure means the area taken to be
loaded by the footings or other load-bearing elements of the building or
structure as depicted in the example in Figure 1.
The example in Figure 1 clarifies that 45º (where depth = distance) is the
maximum angle extending down and outwards from vertical (the angle of
repose) in which the load-bearing elements of a building or structure may
impact upon an infrastructure service or associated structure. This takes into
account the worst possible case for the type and volume of soil.
Performance requirements (P) and Acceptable Solutions (A)
The acceptable solutions of the draft code will only apply to building
development applications for class 1 buildings (such as houses and
townhouses) and class 10 buildings or structures (such as sheds and
retaining walls). If the building development application does not comply with
the acceptable solutions provided by the draft QDC, a concurrence agency
response will be triggered to consider an alternative solution.
Because building development applications for class 2 to 9 buildings (such as
units, offices, shops, warehouses etc) are more complex, they will, in all
cases, need to be referred to the relevant service provider as a concurrence
agency under the SPR. Once referred by a building certifier, the concurrence
agency will assess the application against the performance requirements of
the draft QDC.
This approach provides applicants of reasonably simple building development
applications, such as for a class 1a building, with clear acceptable solutions
that will meet the performance requirements. Providing this path streamlines
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compliance for this type of work. Only complex applications will require further
detailed consideration via a concurrence agency.
There are three performance requirements under the draft QDC.
P1 and A1
P1 relates to the carrying out of building work over or near an infrastructure
service or associated structure (such as a water meter, sewer connection
point, maintenance hole or jump-up). P1 is designed to provide protection of
infrastructure services and associated structures from damage caused by the
load transference of a building or structure.
Under A1, compliance can be achieved by ensuring the load zone (zone of
influence) of the footings or other load-bearing elements of the building or
structure remains away from the infrastructure service.
Alternatively, if the lot size, or soil type do not allow a building or structure to
be built so that underground service pipe/s are not affected, then other
acceptable solutions are provided. For example, the base of the footings of
the building or structure can be extended at least 300 millimetres below the
service or associated structure. If the applicant is unable to meet an
acceptable solution then an alternative solution can be applied. For instance,
an alternative solution will be required if it is proposed that the design of the
building or structure bridges over the top of the infrastructure service.
A1 also provides acceptable solutions for carrying out filling or excavation
work to ensure that this type of work does not place any additional loading on,
or reduce cover to, the service or associated structure. Figure 8 provides an
example to help clarify when excavation work is carried out and how a
minimum cover of 600 millimetres must be maintained to the top, sides and
base of all services. A1 also restricts the use of a vibrating roller within 600
millimetres of a service.
Excavation or filling where the cut or fill is not more than one metre above or
below the natural ground surface for the building or structure is prescribed
under the Building Regulation 2006 as self-assessable building work. Any
excavation or filling exceeding this threshold is deemed assessable work.
P2 and A2
P2 includes provisions to ensure adequate access is provided to infrastructure
services for maintenance and repairs. The acceptable solutions provide
clearance distances (vertical and horizontal) to enable access for work to be
carried out on underground service pipes.
Clearance distances specified by A2 reflect current best practice for
undertaking maintenance and repairs on infrastructure services. Industry
feedback suggests that non-dig technology (electric eels, fibre optic cameras,
water dyes) and/or a Bobcat or small/mini excavator which fit between typical
residential side boundaries are commonly used and would operate within the
specified distances.
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P3 and A3
P3 ensures adequate access must be provided to any associated structures
for maintenance and repairs. P3 includes requirements for clear areas around
structures such as access covers. This ensures ready access is provided for
these structures in the event maintenance or repair is required. P3 also
includes minimum horizontal and vertical clearance distances for maintenance
holes, pits and sewer connection points so that repairers have sufficient
access for machines or other technology to carry out work.
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